ES2566650T3 - Rolled steel plate - Google Patents

Abstract

A laminated steel plate, comprising: a core layer that includes a group of wires formed in a grid form using threads, holes surrounded by the threads, and a resin sheet; and steel plates respectively attached to both sides of the core layer, where the threads have a tensile strength of 601 MPa or more, an opening of the grid wire group, defined by a long side of a rectangle having a maximum area and that internally touches a hole, is equal to or less than ten times the thickness of the steel plates, and the threads are metallic, inorganic or organic threads.

Description

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DESCRIPTION

Rolled steel plate

The present invention relates to a rolled steel plate in which a plate is laminated on both sides of a core layer to reduce its weight.

In various applications, such as parts of automobiles, home appliances, furniture, parts of office automation devices, and the like, there is a wide demand for steel plates that are light, very sharp and shock resistant, and have great maneuverability in terms of shear, curving, deep drawing, extended, and the like, as well as shape stability after processing. In recent years, as a measure against global warming, CO2 emissions are being strictly regulated. In the application to automobile parts in particular, in order to reduce the emission of CO2, excellent performance is required in particular not only in terms of weight reduction but also in terms of stiffness and shock resistance, manageability and stability afterwards. of processing. As a solution for such requirements, several laminated steel sheets have been proposed, as listed below, in which a core layer formed of a resin sheet, a resin sheet with an inorganic filler material, a metal plate processed, a honeycomb structure, a fiber, and / or the like is laminated between the steel plates.

However, the laminated steel plates that have been proposed so far do not combine light weight, high rigidity, high shock resistance, great manageability (manageability in terms of shear, manageability in terms of bending, manageability in terms of deep drawing, manageability as far as extended, and the like), and excellent shape stability after being processed, and the like.

LIST OF DOCUMENTS CITED

PATENT BIBLIOGRAPHY

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patent ograph 1: Japanese patent publication publishes number 51-84880.

Patent 2: Japanese Patent Publication Issue 51-84879.

patent ograph 3: Japanese patent publication publishes number 64-45632.

Patent 4: Japanese Patent Publication Issue Number 6-270325.

Patent ograph 5: Japanese patent publication publishes number 61-123537.

Patent 6: Japanese Patent Publication Issue 52-21089.

Patent ograph 7: Japanese patent publication publishes number 4-299133.

patent ograph 8: Translation of national publication of patent application number 2003-523853.

Patent 9: Japanese Patent Publication Issue No. 62-258939.

patent ograph 10: Japanese patent publication publishes number 62-9951.

Patent 11: Japanese Patent Publication Issue 2000-225664.

Patent 12: Japanese Patent Publication Issue 2001-150616.

Patent document 13: Japanese patent number 2983133.

Patent 14: Japanese Patent Publication Issue Number 9-39139.

patent ograph 15: Japanese patent publication publishes number 2003-96969.

patent ograph 16: Japanese patent publication publishes number 10-305545.

Patent Photograph 17: Japanese Patent Publication Issue Number 10-231580.

Patent 18: Japanese Patent Publication Issue 6-182884.

Patent 19: Japanese Patent Publication Issue 2004-42649.

Patent 20: Japanese patent 3594877.

Patent Photograph 21: Japanese Patent Publication Issue Number 62-264941. 22 patent patent: Japanese patent number 3118066.

patent ograph 23: Translation of national publication of patent application number 2003-508270.

Patent document 24: International publication document number WO2008 / 097984.

Patent document 25: International publication document number WO2007 / 062061.

Patent 26: Japanese Patent Number 2838982.

patent ograph 27: Japanese patent publication publishes number 8-82021.

patent ograph 28: Japanese patent publication publishes number 8-105127.

patent octo 29: Japanese patent publication publishes number 8-20086.

Patent document 30: International publication document number WO2006 / 050610.

Patent document 31: Japanese patent publication publishes number 54-60266.

Patent document 32: Japanese patent publication publishes number 60-149450.

Patent document 33: Japanese patent publication publishes number 60-242052.

DIFFERENT PATENT BIBLIOGRAPHY

Bibliography other than patent 1: D. Mohr, Int. J. Mech. Sci., Vol. 45., P253 (2003).

The present invention is carried out in view of such problems and an object thereof is to provide a laminated steel plate that is light, very sharp and resistant to shocks, and which combines a manageability in terms of

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sheared, curved, deep drawn, extended, and similar, as well as shape stability after being processed.

The inventors of the present application have carried out repeated studies to solve the problems described above, and have found as a result that they form a core layer with a group of wires formed as a grid and a resin sheet and also controlling a resistance to the tension of the threads and an opening of the group of grid threads allows to combine lightness, high rigidity, high shock resistance, excellent damping capacity, manageability, and excellent shape stability after being processed, and have completed The present invention based on this knowledge. Therefore, the above object can be achieved by means of the features defined in the claims.

In accordance with the present invention, it is possible to provide a laminated steel plate that is light, very sharp and shock resistant, and also combines the capacity of damping and manageability in terms of shearing, bending, deep drawing, extended, and the like. , as well as a form stability after being processed.

The invention is described in detail in conjunction with the drawings, in which:

Figure 1 is a cross-sectional view illustrating an example of the overall structure of a rolled steel plate according to a first embodiment of the present invention,

Figure 2A is a plan view illustrating an example of the structure of a group of grid wires according to the embodiment,

Figure 2B is a cross-sectional view illustrating an example of the structure of the grid wire group according to the embodiment,

Figure 3 is a plan view illustrating the structure of an example of modification of the grid wire group according to the embodiment,

Figure 4 is an explanatory view illustrating an example of a bonding effect for a surface layer steel plate by the group of grid wires according to the invention,

Figure 5 is a cross-sectional view illustrating the structure of an example of modification of the rolled steel plate according to the embodiment,

Figure 6 is a cross-sectional view illustrating an example of the overall structure of a rolled steel plate according to a second embodiment of the present invention,

Figure 7 is a cross-sectional view illustrating an example of the overall structure of a rolled steel plate according to a third embodiment of the present invention,

Figure 8A is an explanatory view illustrating an example of a bending deformation behavior of the rolled steel plate according to the first embodiment of the present invention, and Figure 8B is an explanatory view illustrating an example of a behavior of deformation of bending of the rolled steel plate according to the third embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in greater detail with reference to the attached figures. Note that in this report and the drawings, components that have substantially the same functional structures receive the same reference numbers, and duplication of the descriptions is omitted.

[First realization]

[Structure of rolled steel plate]

First, the overall structure of a rolled steel plate according to a first embodiment of the present invention will be described with reference to Figure 1. Figure 1 is a cross-sectional view illustrating an example of the overall structure of the rolled steel plate 1 according to this embodiment.

As illustrated in Figure 1, the rolled steel plate 1 according to this embodiment has a structure in which steel plates 5 (5A, 5B) (hereinafter referred to as "surface layer steel plates") are respectively laminated to both sides of a core layer 10. That is, the laminated steel plate 1 is laminated on the surface layer steel plate 5A, and the surface layer steel plate 5B is additionally laminated thereon. The core layer 10 is formed by one or more groups 11 of grid wire, and one or more resin sheets 13 of a resin base material formed in the form of a sheet. When the core layer 10 is formed by two or more groups 11 of grid wire and two or more resin sheets, these groups 11 of wire and resin sheets 13 are structured to be laminated one upon another. Here, Figure 1 illustrates an example in which a core layer 10 has a structure such that a resin sheet 13, a group 11 of grid wire, a sheet of resin 13, a group 11 of grid wire, and A resin sheet 13 is laminated in this order from the face of the surface layer steel plate 5. In addition, it is not necessary for the groups 11 of grid wire and the resin sheets 13 to be laminated in order, and the core layer 10 can have a structure such that at least the groups 11 of grid wire or the sheets 13 of resin are laminated sequentially.

Also, as will be described in detail below, on the laminated steel plate 1 according to this embodiment, preferably the wire forming the groups 11 of grid wire is a steel wire having a

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Carbon content of 0.24% by mass or more. In addition, the opening of the grid wire groups 11 must be equal to or less than ten times the thickness ts of the surface layer steel plate 5. Hereinafter, the respective members forming the laminated steel plate 1 will be described in detail.

(Structure of the grid wire group)

First, the structure of a group 11 of grid wires according to this embodiment will be described with reference to Figure 1, Figure 2A and Figure 2B. Figures 2A and 2B are views illustrating an example of the structure of the grid wire group 11 according to this embodiment. Figure 2A illustrates a plan view and Figure 2B illustrates a cross-sectional view.

As illustrated in Figure 2A, the grid wire group 11 is formed in a grid shape by using threads for vertical threads 111 and horizontal threads 113. Here, the vertical threads 111 refer to threads that extend in a longitudinal direction (vertical direction in the example illustrated in Figure 2A) from among all the threads that form the group 11 of grid threads. Additionally, the horizontal threads 113 refer to threads that extend in the width direction (horizontal direction in the example illustrated in Figure 2A) orthogonal to the longitudinal direction of all the threads that form the thread group 11 of grid. Furthermore, in the example illustrated in Figure 2A, an opening w (wl, wh) of the group 11 of grid threads refers to a distance between two vertical threads 111 or adjacent horizontal threads. In some cases, a distance between two adjacent vertical threads 111 is referred to as an opening wl, and a distance between two adjacent horizontal threads 113 is referred to as opening wh, to distinguish them. When the group 11 of grid wires has square openings, wl = wh is met. Furthermore, in the group 11 of grid wires, holes 115 (squares) exist respectively in portions surrounded by the vertical wires 111 and the horizontal wires 113, and due to the existence of these holes 115, the core layer 10 may have a reduced weight compared to a steel plate, an Al plate, or the like. In addition, the sum of the diameter (cable diameter) d of the wires that form the group 11 of grid wires and the opening w is referred to as a passage (grid passage) p. Note that the opening w described below is defined by a long side of a rectangle that has a maximum area that internally touches a hole and indicates an average of the long sides in ten arbitrarily chosen holes, and indicates, when the threads are arranged in parallel, an average range of threads arranged in parallel.

In addition, the thickness tN of the grid wire group 11 is represented by a distance between a bending portion 111a and another bending portion 111b of the vertical threads 111 or the horizontal threads 113. In the example illustrated in Figure 2B, the thickness tN of the group 11 of grid threads is represented by a distance between an upper bending portion 111a and a lower bending portion 111b of the horizontal wire 113. As described above, in the laminated steel plate 1 according to this embodiment, the core layer 10 is formed by one or more groups 11 of grid wire and one or more sheets 13 of resin. The thickness of the core layer 10 differs depending on how the group 11 of grid wires and the resin sheet 13 are laminated. When the group 11 of grid wires is not embedded in the resin sheet 13, the thickness tc of the core layer 10 is tc = nx tN + n2 x tR, where the number of groups 11 of grid wire is ni, the thickness of the resin sheet 13 is tR, and the number of resin sheets 13 is n2. On the other hand, when embedded, the thickness is tc = n2 x tR. Also, when it is partially embedded, among them there is tc.

<Thread tensile strength>

Even when an opening that allows weight reduction is secured, a core layer resistance is ensured if the tensile strength of the threads that form the grid wire group is 601 MPa or greater. As a result, after subjecting the rolled steel plate to intense processing such as bending or deep drawing, the core layer is not destroyed and is maintained in conditions. Preferably, the tensile strength of the wires is 1000 MPa or greater, more preferably 2000 MPa or greater, and in this range the effects described above are ensured and a shock absorption operation can be obtained. On the other hand, in terms of manageability by shearing and bending, preferably the tensile strength of the threads is 6000 MPa or less. When the tensile strength of the wires is greater than 6000 MPa, the shear strength of the core layer increases, and the bending force and shear force applied to both a surface layer and a bonding layer between a surface layer and an adhesive layer increase when the rolled steel plate is curved, easily destroying the surface layer or delaminating and destroying the adhesive layer.

<Diameter of the threads>

The diameter d of the threads (thread diameter d) is not particularly limited, it may be equal to or less than a necessary thickness of the core layer 10 from the point of stiffness and shock resistance that is necessary depending on the application of the laminated steel plate 11, and can be adequately determined depending on the characteristics (plate density, stiffness, shock resistance, etc.) of the laminated steel plate 1 that should be prioritized for each application. For example, when the plate density of the laminated steel plate 1 is particularly important, the diameter of the following expression (1) and the expression (2) can be determined according to the opening of the group 11 of grid wires and the population density of plaque as the objective of core layer 10. Additionally, when the strength of the laminated steel plate 1 is particularly important, the diameter d of the wire can be determined from the following expression (3) and expression (2) according to an Mpobjective bending moment in a deformation range plastic as a factor

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Dominant shock resistance.

population> 7.8 x (1 - Vaire) x n ■■■ (1)

Vaire = W2 / (W + d) 2 ... (2)

Objective <1 / 40ys [(ts + tc) - tc] + 1/8 (1 - Vaire) Oyc ... (3)

(In the previous expressions (1) to (3), population denotes the target plate density of core layer 10, Vaire denotes the volume of hole portion 115 in core layer 10, n denotes the number of laminations of group 11 of grid threads, w denotes the opening of group 11 of grid threads, Mpob denotes the moment of objective bending, oys denotes the elastic limit of the surface layer steel plate 5, ts denotes the thickness of the plate 5 of surface layer steel, tc denotes the thickness of the core layer 10, and d denotes the wire diameter of the grid wire group 11).

<Grid cable group opening>

In the laminated steel plate 1 according to this embodiment, it is necessary that the opening w of the grid wire group 11 be equal to or less than ten times the thickness ts of the surface layer steel plate 5. That the opening w of the group 11 of grid threads is equal to or less than ten times the thickness ts of the surface layer steel plate 5 is decided according to the considerations of the present inventors. The case of a tensile deformation of the laminated steel plate 1 having the core layer 10 in which a tensile strength relationship between the wires such as the core material of the core layer 10 and the plate is assumed 5 surface layer steel is equal to or less than 1/50 (which is a value with greater tensile strength in the denominator). In this case, by means of an FEM analysis (Finite Element Method), it was found that when the length of one side of the hole 115 (the opening w) that exists in the core layer 10 is greater than ten times the thickness of the surface layer steel plate 5, the stresses are concentrated in a portion located above the hole 115 in the surface layer steel plate 1, and the surface layer steel plate 5 soon fractures. In the surface layer steel plate 5, the substantial thickness of the steel plate differs between the portion above the holes 115 of the core layer 10 and a portion located above the threads (vertical threads 111 and horizontal threads 113 ). Consequently, the resistance (tensile strength and elastic limit) in the portion above the holes 115 becomes smaller than the resistance of the portion above the threads. As a result, when a tensile strain or compression strain is applied to the laminated steel plate 1, the stresses are concentrated in the portion above the holes 115 which has a low resistance in the surface layer steel plate 5, The fracture elongation decreases, and therefore the manageability increases.

By decreasing the opening w of the group 11 of grid threads to be equal to or less than ten times the thickness ts of the surface layer steel plate 5, the tensions that are concentrated in the portion above the hole 115 of the plate 5 of surface layer steel during tensile or compressive deformation of the laminated steel plate 1 can be dispersed, and the fracture elongation of the surface layer steel plate 5 can be increased. As a result, the manageability of the laminated steel plate 1 can be improved, and the processing stability of the laminated steel plate 1 can be ensured even when intense processing such as bending or deep drawing is applied. Also, to sufficiently disperse the tensions, preferably the opening w of the group 11 of grid wires is equal to or less than 3.5 times the thickness ts of the surface layer steel plate 5.

Furthermore, when the opening w of the group 11 of grid wires is smaller, the stresses that are concentrated in the portion above the holes 115 of the surface layer steel plate 5 can be dispersed. In addition, if a fracture occurs in the surface layer steel plate 5, this fracture is confined to the hole 115 which has the small opening w and is difficult to transmit to other portions. Therefore, the smaller the opening w of the group 11 of grid threads, the more it is preferred in terms of handling. On the other hand, when the opening w of the group 11 of grid wires is small, the plate density of the core layer 10 increases due to the above expressions (1) and (2). Accordingly, considering a view of ensuring a light weight, preferably, the opening w of the group 11 of grid threads is equal to or greater than 0.5 times the thickness ts of the surface layer steel plate 5.

From a viewpoint of achieving excellent workability and processing stability in a manner compatible with a light weight to a degree greater than that described above, preferably, the opening w of the group 11 of grid threads is equal to or greater than 0.5 times and equal to or less than once the thickness ts of the surface layer steel plate 5.

Furthermore, in this embodiment, as the group 11 of grid threads that forms a grid is contained in the core layer 10, it is easier to control the size of the holes than when a punching, embossing, or the like is carried out in a metal plate material or the like to form the holes. That is, it is easy to control the length of one side of the hole 115 (opening w) to adjust it to the small size equal to or less than ten times the thickness ts of the surface layer steel plate 5. Accordingly, with the rolled steel plate in accordance with the present

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Invention, a cost reduction, an improvement in productivity, and the like are also possible.

<Grid wire group formation method>

In a method of forming the group 11 of grid threads, provided that the conditions described above of tensile strength and opening of the threads are satisfied, a way of interlacing, a way of weaving, or the like, and Any form of rhomboidal, hexagonal, rectangular, and the like can be used. As groups 11 of square grid threads, there is the group of interlocking grid threads, the group of corrugated grid threads, etc. Specific examples of the group of interlocking grid threads include simple interlacing, diagonal interlacing, mat interlacing, corresponding mat interlocking, and the like. In addition, specific examples of the group of wavy grid threads include corrugated interlocking, corrugated interlocking interlocking, double corrugated interlacing, flat corrugated interlacing, ton-cap interlocking ton-cap screen, interlocking groove screen, and the like. In addition, the method of forming the group 11 of grid wires can be the solid state joint, such as by welding instead of by interlocking or braiding. That is, the vertical wires 111 and the horizontal wires 113 may be joined by a solid state joint such as welding to form a grid. Also, as a method for interlacing the group of grid threads, three-dimensional interlacing can be used instead of two-dimensional interlacing.

Among the training methods described above of the group 11 of grid threads, the group of grid threads with simple interlacing is preferred from the point of view of ease of manufacturing and economic efficiency, and the group of grid threads with interlacing Flat top is preferred from a viewpoint of the joint property of the surface layer steel plate 5 and the core layer 10.

Furthermore, in group 1 of grid wires according to this embodiment, ligatures (wires) can be added in an oblique direction to the square openings using the wires described above. This oblique address refers to a direction that crosses both vertical threads 111 and horizontal threads 113. Specifically, for example, ligatures (threads) in a direction according to 15 °, 30 °, 45 ° or the like can be added to the group 11 of square grid threads with respect to the direction of the vertical threads 111 or the horizontal threads 113.

<With regard to the bonding effect for the surface layer steel plate by the grid wire group>

Figure 3 is a plan view illustrating the structure of an example of modification of the grid wire group according to this embodiment. In this embodiment, to obtain a bonding effect, which will be described later, so that the surface layer steel plate 5 is sufficiently shown by the group 11 of grid wires, such as a group 11 'of grid wires illustrated in Figure 3, preferably, in particular, ligatures (threads) 117 according to an orthogonal direction at 45 ° in relation to the directions of the vertical threads 11 and the horizontal threads 113 are added to the group of square grid threads formed by the threads 111 vertical and the horizontal threads 113.

Here, the bonding effect for the surface layer steel plate 5 by the group 11 of grid wires will be described with reference to Figure 4. Figure 4 is an explanatory view illustrating an example of the bonding effect for the plate of surface layer steel by the grid wire group according to this embodiment. Note that in Figure 4, vertical threads 111 and horizontal threads 113 are shown by solid lines for ease of explanation.

In this embodiment, the group 11 of grid wires is contained in the core layer 10. It is assumed that, as illustrated in the left view of Figure 4, the group 11 of grid threads is, for example, processed by means of a force T along the direction of the vertical threads 111. Then, as illustrated in the right view of Figure 4, a tensile deformation occurs in the direction of the vertical threads 111, while no tensile deformation occurs in the direction of the horizontal threads 113. That is, the vertical opening wl2 after the tensile processing is larger than the vertical opening wl1 before the tensile processing, but the horizontal opening wh2 after the tensile processing is substantially the same as the horizontal opening wh1 before the tensile processing, and the horizontal opening almost does not change before and after the traction processing.

Therefore, when the core layer 10 has the group 11 of grid threads, if the threads (vertical threads 111 and horizontal threads 113) that form the group 11 of grid threads are partially arranged perpendicular to the deformation direction at compression or tensile deformation during bending, the threads that form the group 11 of grid threads do not deform, and a Poisson deformation effect of joining the surface layer steel plate 5 is obtained. Through this bonding effect, the Young Es module of the surface layer steel plate 5 can be increased, and it is possible to efficiently increase the rigidity EI of the laminated steel plate 1 represented by the following expression (4). Furthermore, said bonding effect appears by the use of the group 11 of grid wires, and cannot be obtained, for example, by punching a metal plate material or the like.

EI = (1/12) It is [(ts + tc) 3 - tc3] + 1 / 12Ectc3 ... (4)

(In the previous expression (4), EI is the rigidity of the rolled steel plate 1, It is Young's modulus of the surface layer steel plate 5, Ec is Young's modulus of the core layer 10, ts is the thickness of the plate 5 of

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surface layer steel, and tc is the thickness of the core layer 10).

In this embodiment, by arranging the threads (vertical threads 111 and horizontal threads 113) perpendicular to the deformation direction as described above while ensuring isotropic, the bonding effect of the layer 5 steel plate Superficial is presented in a wide deformation direction. Consequently, as the group of grid wires contained in the core layer 10, preferably, the group 11 'of grid wires is used where ligatures (wires) 117 in an oblique direction according to 45 ° with respect to the direction of the vertical threads 111 and the horizontal threads 113 are added to the group of square grid threads formed by the vertical threads 111 and the horizontal threads 113.

<Lamination of grid wire groups>

As described above, there may be a group 11 of grid wires contained in the core layer 10 according to this embodiment, or two or more groups of grid wires may be laminated. In addition, one or more groups 11 of grid wires can be arranged randomly two-dimensionally. In addition, when two or more groups are laminated, the case in which the resin sheet 13 is laminated between two groups 11 of grid wires is included. In particular, in this embodiment, when n layers (n is two or more) of groups 11 of grid wires in the core layer 10 are laminated to increase the isotropy of the core layer 10, it is possible to shift the direction of the threads that form the group 11 of grid threads of each layer a certain direction according to the angles 360 / 3n or more and 360 / n or less between the adjacent layers of the groups 11 of grid threads, to laminate the groups 1 of grid threads of the respective layers. To illustrate said method of lamination, there is a method for laminating four layers so that in the group 11 of lower grid threads, the groups 11 of grid threads as top layers thereof are laminated rotated each of them 45 °. From a viewpoint of increasing the isotropic, preferably, the number n of layers of groups 11 of grid threads is increased and the groups 11 of grid threads are laminated each being rotated small angles (360/3 ° up to 360 / 3n each). On the other hand, from an economic rationality point of view, a higher limit is preferably established for the number of layers. Therefore, preferably, the number of groups 11 of grid threads to be laminated is greater than two and less than 20. Furthermore, when two or more groups 11 of grid threads are laminated, the respective groups of grid threads can be arranged in parallel without rotation.

Here, with reference to Figure 5, a preferred example of the case will be described in which the core layer 10 has a structure in which three or more groups 11 of grid wires are laminated. Figure 5 is a cross-sectional view illustrating the structure of a modified example of a 1 'plate of rolled steel according to this embodiment.

As illustrated in Figure 5, the core layer 10 on the rolled steel plate 1 'has a structure in which a resin sheet 13, a group 11A of grid wires, a resin sheet 13, a group 11B of grid wires, a resin sheet 13, a group 11C of grid wires, and a resin sheet 13 are laminated in this order from the side of the surface layer steel plate 5. Then, the opening wa of the two groups 11A, 11C of grid threads arranged on one side near the surface layer steel plate 5 is smaller than the opening wb of the group 11B of grid threads arranged on a side away from 5 plate of surface layer steel. Therefore, it is preferred that the opening of the group of grid threads disposed on a remote side with respect to a central position in the direction of the thickness of the core layer is smaller than the opening of the group of grid threads arranged in a near side with respect to the central position in the direction of the core layer thickness. This is due to the following reason.

Generally, a central portion in a direction of the thickness of a steel plate has a relatively small contribution to stiffness or shock resistance. Accordingly, the group 11B of grid threads with a large opening and a small resistance is arranged in the central portion in the direction of the thickness of the core layer 10 of the laminated steel plate 1 which has a contribution to stiffness and relatively low shock resistance to further reduce weight. On the other hand, on the side of the surface layer steel plate 5 that has a relatively high contribution to stiffness and shock resistance, groups 11A, 11C having a small opening and high strength are arranged, to ensure stiffness and shock resistance. Therefore, in the laminated steel plate 1 'according to the modified example of this embodiment, the opening wa of the groups 11A, 11C of grid wires on the side of the surface layer steel plate 5 becomes relatively more small, and the opening wb of the group 11B of grid wires arranged on the central side of the core layer 10 becomes relatively larger.

Furthermore, when a plurality of groups 11 of grid wires and resin sheets 13 are laminated, an adhesive or the like, which will be described later, can be used to bond the respective groups 11 of grid wires and the resin sheets 13. In addition, when two groups 11 of grid wires are joined directly, a bonding force with respect to shear deformation can be added by welding or interlocking a joint point to increase a frictional force at the joint point.

<Thread material>

In this embodiment, for the threads that form the grid, threads with a tensile strength of 601 MPa or higher will be sufficient, and the following metallic, inorganic, organic threads are conceivable. Among others, the threads

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Metals are more preferred because, when the deformation behaviors are similar between the core layer and the surface layers, and a large deformation such as a bend is applied, the core layer and the surface layers are integrally deformed therein. . The most preferred from this point of view is a steel cable. As metal cables, there are carbon steel steel cables whose carbon content is 0.24% or more, austemotic stainless steel based on ferrite and the like, copper wires based on copper, tin, bronze, phosphor bronze and similar, nickel wires, nickel / copper alloys, nickel / chrome, nickel / chrome / molybdenum and the like, titanium wires, aluminum wires, and the like. In addition, in the case of iron-based threads, public processes such as the coating such as zinc coating, Ni coating, tin coating, copper coating, or the like can be carried out. In addition, as inorganic threads, there are inorganic fibers such as those based on PAN, step-based carbon fibers, glass fibers, alumina fibers, and silicon carbide fibers. In addition, as organic threads, there are high strength and high modulus organic fibers such as aramid fibers, polyarylate fibers, high strength polyolefin fibers (for example, high strength fiber called high polymer polyethylene fibers, or the like ).

<Composition of steel wires>

When steel wires are used for group 11 of grid wires in this embodiment, it is preferred that the carbon content thereof be 0.24% by mass or more. Being the carbon content of steel wires of 0.24% by mass or more, the tensile strength of steel wires can be ensured. For example, when the density of steel wires in the core layer 10 decreases to a required plate density (mass ratio of the steel plates in the core layer 10), it is possible to ensure tensile strength and deformation resistance of the group 11 of grid threads of the core layer 10 when the rolled steel plate 1 is processed or required in a product after being processed. Consequently, it is possible to reduce the weight of the laminated steel plate 1 sufficiently while maintaining high rigidity and shock resistance of the laminated steel plate 1.

On the other hand, when the carbon content of the steel wires is less than 0.24% by mass, the tensile strength and the elastic limit of the steel wires decrease. Therefore, unless the strength of the steel wire of the core layer 10 increases and is reinforced, the necessary tensile strength and elastic limit of the core layer 10 cannot be ensured, and the weight of the plate 1 rolled steel cannot be reduced sufficiently. In addition, as steel wires, JIS G 3506-2004, JIS G 3502-2004, or the like can preferably be used, although steel wires are not limited thereto and any steel wires that satisfy the composition above can be used described as steel wires to form the group 11 of grid wires of this embodiment.

Furthermore, from a viewpoint of further improving the tensile strength and elastic limit of the core layer 10, it is preferred that the carbon content of the steel wires be 0.60% by mass or more. Consequently, even when the core density of the core layer 10 falls more than conventional, the tensile strength and the elastic limit of the core layer 10 can be sufficiently secured, and therefore it is possible to achieve a high level lightweight compatible with stiffness and shock resistance. On the other hand, when the carbon content of the steel wires is too much, the group 11 of grid wires of the core layer 10 becomes too hard. Therefore, it can happen that the control of the opening of the group 11 of grid threads at intervals as small as ten times the thickness of the surface layer steel plate 5 becomes difficult. From this point of view, it is preferred that the carbon content of the steel wires is 0.96% or less.

(Structure of the resin sheet)

Next, the structure of the resin sheet 13 in accordance with this embodiment will be described. As the base material for the resin sheet 13 according to this embodiment, there is no particular limitation for the type of resin. A resin sheet formed by a thermoplastic resin, a thermosetting resin, an elastomeric body, or the like, or a mixture of one or more of the foregoing can be used. Specifically, examples of the type of resin for resin sheet 13 include polystyrene general purpose vinyl based resin sheets, polymethyl methacrylate, hard or soft vinyl chloride, high density or low density polyethylene or linear low density, polypropylene, and the like, resin sheets based on inonomer elastomers, polyolefin based elastomer, styrene based elastomer, or the like, polycarbonate polyester resin sheets, polyethylene terephthalate, polybutylene terephthalate, polyarylate, or the like, polyamide resin sheets of Nylon-6, Nylon-66, Nylon-12, or the like, polyimide resin sheets, polyester carbonate resin sheets, thermoplastic resin sheets of polyphenylene ether condensation, or the like, thermoplastic resin sheets of epoxy resin, phenol resin, urea resin, polyester melanin resin, or the like, and a mixture thereof. Furthermore, with the purpose of reforming the formability of the sheet, the impact resistance and the like of the resin sheet 13, it is possible to mix in the above-described resin a condensation polymer of polystyrene vinyl halide resin, polymethyl methacrylate , hard or soft vinyl chloride, or the like, general purpose resins based on linear or high density or low density polyethylene vinyl, polypropylene, amorphous polyolefin, or the like, ionomer elastomer based resins, polyolefin based elastomer of copolymer of ethylene propylene, copolymer of ethylene butene, copolymer of ethylene vinyl acetate, or the like, elastomer based on styrene, or the like, polycarbonate or the like.

As the resin sheet 13 is reinforced with the group 11 of grid threads, it has excellent stability of

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It forms at high temperatures compared to resin sheets that do not include a reinforcing material such as group 11 of grid wires. Therefore, although it is not necessary to specify the heat resistance of the base material of the resin sheet 13, when it is an amorphous resin sheet 13, it is preferred that its glass transition temperature is 100 ° C or greater. In addition, when it is a crystalline resin sheet 13, it is preferred that its melting point be 120 ° C or higher. In a resin sheet 13 using a base material whose glass transition temperature and melting point (crystallization temperature) are outside such temperature ranges, progressive deformation occurs locally during hot painting, and corresponding irregularities can occur to the orifice portions 115 of the group 11 of grid threads on the surface of the surface layer steel plate 5.

Furthermore, to ensure the adhesion of the surface layer steel plate 5 and the group 11 of grid threads with the resin sheet 13, it is preferred that the resin sheet 13 contains a resin into which a polar group is introduced, as a carboxyl group, an amphipidated acid group, a phosphate group, sulfonic group, metal salt or an active group thereof, epoxy group, hydroxyl group, amino group, carbonyl group, ester linkage group, linkage group carbonate, amide binding group, imide binding group, or the like.

For the above reasons, the most preferred resin base material for resin sheet 13 is a polyester resin or polyamide resin, and more specifically, polyethylene terephthalate, polybutylene terephthalate, nylon-6, nylon-66, nylon -12, or the like are particularly preferred. The resin sheet 13 using such resin base material exhibits heat resistance and favorable adhesion between the surface layer steel plate 5 and the group 11 of grid wires can be secured with the resin sheet 13 due to a group polar such as an ester group, amide group, or end carboxyl group, hydroxyl group, amino group, or the like in a chain of molecules. In addition, a resin sheet 13 of this type exhibits an excellent balance of mechanical properties such as strength and hardness. More preferably, it is a resin sheet 13 that uses a polyester resin or polyamide resin that uses a carboxyl group remains 70% or more of a chain end of molecules as the resin base material. Among several replacement elements, the carboxyl group has the greatest adhesion with the surface layer steel plate 5 and the group 11 of grid threads, and therefore when more carboxyl group contains the resin base material, the greater the adhesion of the resin sheet 13 with the surface layer steel plate 5 and the group 11 of grid threads. In addition, the above-described resins are obtained by polymerization by sealing one end with a chemical compound containing a 2-functional or more carboxyl group, in which one more monomer is attached which contains a carboxyl group, or the like. In addition, the remaining ratio of the end carboxyl group can be calculated from a ratio between an end root obtained by a neutralization dosage of a resin base material, dissolved in a solvent having an affinity, with an alkaline solution. , and an end root calculated from an average molecular weight obtained by SEC (Size Extrusion Cromatography, Extrusion Chromatography).

Also, in the resin sheet 13 according to this embodiment, preferably a foam is used as the resin base material to achieve a weight reduction effect. In this case, the resin expansion ratio is preferably two or more, more preferably four or more, and even more preferably ten or more, so that it has a sufficient weight reduction effect. On the other hand, the foam expansion ratio is preferably 15 or less. This is because although it is possible that there is an effect of improving the compressive strength of the core layer 10 by the reinforcing effect of the group 11 of grid wires even when the expansion ratio is greater than 15, the elastic modulus and the shear strength decreases significantly, easily resulting in a shear failure or surface undulation when the rolled steel plate 1 is processed.

When foam is used as the resin base material of the resin sheet 13, it is preferable that the bubbles be dispersed so that the distance between adjacent bubbles is 0.1 pm or greater and 5 pm or less. By making the distance between adjacent bubbles 0.1 0.1 or greater, the stresses are concentrated at the interface between the finely dispersed bubbles and a matrix resin, and as a result the stresses can be dispersed throughout the entire plate 1 of rolled steel In addition, by controlling the distance between adjacent bubbles to be 5 pm or less, the area of plastic deformation formed by the stresses that are concentrated at the interface between the bubbles and the matrix resin can be continuous, thus avoiding the transmission of cracks and improving the hardness of the resin sheet 13. As a result, even when the laminated steel plate 1 is subjected to an intense processing in fno, it is possible to prevent the destruction by the resin sheet 13 by using the foam. A more preferred range of distance between adjacent bubbles is 2.0 pm or less, more preferably 1.0 pm or less. The smaller the distance between adjacent bubbles, the easier it will be for the area of plastic deformation to become continuous and the easier to improve the hardness of the resin sheet 13.

Also, preferably, the average bubble bubble diameter used as the resin base material of the resin sheet 13 is controlled to be 0.1 pm or greater, and 10 pm or less. When the average bubble diameter is less than 0.1 bubble, it is difficult to concentrate stresses at the interface between the bubbles and the matrix resin. On the other hand, when the average bubble diameter is greater than 10 bubble, it is difficult to control the distance between adjacent bubbles so that it is in the preferred range described above. From this point of view, the average bubble diameter is preferably 5 pm or less, more preferably 3 pm or less.

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Here, the distance between adjacent bubbles and the average bubble diameter can be evaluated by observing a cross-section of the resin sheet 13 with an electron microscope or the like, and performing image processing or the like. Specifically, a microscope image of a cross-section is digitized, and the average bubble diameter can be calculated as an average value of an equivalent circular diameter as a diameter when replaced by the area of a circle. In addition, the distance between adjacent bubbles can be estimated from a distance between bubble circumferences according to a straight line joining the centers of the bubbles.

In addition, the resin sheet 13 according to this embodiment may be subjected to a publicly known surface treatment such as a corona treatment, plasma treatment, or UV treatment, to increase a critical surface tension, thereby improving adhesion with the plate 5 steel surface coating and adhesive. From a viewpoint of ensuring adhesion with the surface layer steel plate 5, it is preferred that the critical surface tension be controlled to be 45 dyn / cm (mN / m) or greater by surface treatment before the resin sheet 13 be laminated. Furthermore, when the resin sheet 13 is laminated by an adhesive, the use of an adhesive, which will be described later, is preferred for adhesion and stability in a heat resistant manner.

Here, in this embodiment, preferably, the group 11 of grid wires is embedded in the resin sheet 13. Here, the expression "the group 11 of grid wires is embedded in the resin sheet 13" means a state in which a portion corresponding to 90% or more of the volume of the entire group 11 of resin wires is wrapped in the resin sheet 13. By embedding the group 11 of grid threads in the resin sheet 13, the elastic modulus and tensile strength of the core layer 10 can be increased, and stiffness and shock resistance can be increased. Furthermore, by embedding the group 11 of grid threads in the resin sheet 13, a contact is achieved between the surface layer steel plate 5 and the group 11 of grid threads or between the groups 11 of grid threads through of resin sheet 13. Thus, the resin sheet 13 can play the role of shock absorbing member to improve the damping performance of the laminated steel plate 1. In addition, by embedding the group 11 of grid threads in the resin sheet 13, the weight can be reduced while ensuring a greater thickness than in the case of only one group 11 of grid threads. Furthermore, even when using the group 11 of grid wires having the hole portions 115, the hole portions 115 can be filled with the resin, and therefore the contact area between the core layer 10 and the plate 5 of Surface layer steel can be increased to improve adhesion between the core layer 10 and the surface layer steel plate 5. In addition, corrosion can be avoided by suppressing the adhesion of water to the inside of the surface layer steel plate 5 due to the condensation of mist or the like, and therefore also the corrosion resistance of the 1 plate of rolled steel.

In addition, it is preferable that the thickness of the resin sheet 13 is greater than 40% of the thickness of the group 11 of grid threads. When the thickness of the resin sheet 13 is equal to or less than 40% of the thickness of the group 11 of grid threads, it may occur that the laminated steel plate 1 does not have sufficient damping performance.

(Structure of the surface layer steel plate)

The surface layer steel plate 5 according to this embodiment is not particularly limited. Specifically, it is possible to use, for example, a steel plate such as a steel plate coated with tin or thin tin, a steel plate treated with electrolytic chromium acid (steel without tin), a steel plate coated with nickel , or similar, a hot dipped steel plate such as a galvanized steel plate obtained by hot dipping, a steel plate obtained by hot dipping coated with galvanized iron alloy, a steel plate obtained by hot dipping coated with magnesium-aluminum-zinc alloy, a steel plate obtained by hot dipping coated with aluminum-silicon alloy, a steel plate obtained by hot dipping coated with lead-tin alloy, or similar, a plate steel with an electrolytic coated steel plate surface treatment or the like, such as an electrolytic galvanized steel plate, a steel plate coated with electrolytic galvanization, a steel plate coated with electrolytic iron alloy, a chrome alloy coated steel plate with electrolytic galvanization, or the like, a steel plate laminated with a plate, a plate of hot rolled steel, a stainless steel plate, or the like. In addition, the surface layer steel plate 5 can be a steel plate with a surface treatment such as a painted steel plate, a printed steel layer, a laminated steel layer with a film, or the like.

In addition, it is possible to laminate the core layer 10 between different types of steel plates. Specifically, in an application where a deep or similar deep bending or drawing is necessary, it is possible to laminate the core layer 10 between steel plates with different resistances, a soft steel is used on a surface that has a small radius of curvature and that It is difficult to process, and a high strength steel is used for the other surface to ensure strength.

Furthermore, it is possible to carry out a publicly known surface treatment on the surface of the surface layer steel plate 5 in accordance with this embodiment, to improve the adhesion and corrosion resistance. Examples of such surface treatment include chromate treatment (reactive type, type of

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coating, electrolytic), phosphate treatment, organic resin treatment, and the like, although not limited thereto.

(Union of resin sheet and surface layer steel plate or grid wire group)

Next, the union of the resin sheet 13 and the surface layer steel plate 5 or the group 11 of grid wires will be described.

The joining of the resin sheet 13 and the surface layer steel plate 5 or the group 11 of grid wires according to this embodiment may mean joining by direct lamination of the resin sheet 13 onto the steel plate 5 of surface layer or group 11 of grid threads or bonding by laminating an adhesive layer between the surface layer steel plate 5 or group 11 of grid threads and the resin sheet 13. When the adhesive layer is laminated, it is necessary for the adhesive to have an affinity with both the resin sheet 13 and the surface layer steel plate 5 or the group 11 of grid threads. A criterion regarding the affinity of the adhesive with the resin sheet 13 is that a difference in the solubility parameter between the adhesive and the resin sheet 13 is 6 MJ / m3 or less. Alternatively, if the resin sheet 13 has a polar group, one criterion is that a functional group (including a coupling group) capable of forming, with this polar group, a chemical bond such as a covalent bond, a joint of hydrogen, an effect of ion interaction, a union of coordinates, or the like, or a physical or similar union that is not accompanied by the movement of charges, is introduced into the adhesive. The solubility parameter can be estimated by the Fedors or Small method or the like from a chemical or similar structure of a forming unit. The difference in the solubility parameter between the adhesive and the resin sheet 13 is preferably 6 MJ / m3 or less, more preferably 3 MJ / m3 or less, even more preferably 2 MJ / m3 or less. The smaller the difference in the solubility parameter between the adhesive and the resin sheet 13, the more the compatibility between the two and the initial adhesion improves.

On the other hand, a suitable adhesion between the resin sheet 13 in practice and the adhesive can be evaluated by adhesion of two resin sheets 13 with an adhesive and the measurement of a separation resistance T. In this case, the separation resistance T is preferably 20 N / cm or greater, more preferably 30 N / cm or greater, even more preferably 45 N / cm or greater, and even more preferably 60 N / cm or greater. In addition, when the separation resistance is less than 20 N / cm, the initial adhesion resistance just after the surface layer steel plate 5 or the group 11 of grid threads has been laminated is small, and a delamination at the interface between the resin sheet 13 and the adhesive during processing or heating after processing.

The practical affinity of the surface layer steel plate 5 or the group 11 of grid threads with the adhesive can be assessed by a separation test T (JlS Z 0238) of a test piece obtained by joining two plates 5 of surface layer steel or two groups 11 of grid wires with an adhesive. The separation resistance T in this case is preferably within a similar resistance range between the resin sheet 13 and the adhesive. Specifically, in a manner similar to the interface between the resin sheet 13 and the adhesive, a separation resistance T of 20 N / cm is preferred. When the separation resistance T is less than 20 N / cm, the interface between the surface layer steel plate 5 (or the group 11 of grid wires) and the adhesive makes it difficult to adhere, and delamination can occur during processing or heating plate 1 of rolled steel. In addition, the separation resistance T of the surface layer steel plate 5 or the group 11 of grid wires with the adhesive is more preferably 30 N / cm or greater, still more preferably 45 N / cm or greater, and even more preferably 60 N / cm or greater.

In addition, to retain stability in a heat resistant manner after being processed, a G 'module of adhesive storage at 100 ° C to 160 ° C is preferably 0.05 MPa or greater and 100 GPa or less. When the laminated steel plate 1 is formed, residual stresses occur at the interface between the surface layer steel plate 5 (or the group 11 of grid wires) and the adhesive. When the formed product of the rolled steel plate 1 is heated to the described temperature, if the adhesive storage module G 'is less than 0.05 MPa, the adhesive layer gradually deforms due to these residual stresses, which may lead to the destruction of the adhesive layer or the beginning of delamination of the adhesive layer. From this point of view, the adhesive storage module G 'at 100 ° C to 160 ° C is more preferably 1.0 MPa or greater, even more preferably 5 MPa or greater. On the other hand, when the adhesive storage module G 'is greater than 100 GPa, the room temperature storage module G' increases, and therefore the processing capacity decreases. Consequently, it can happen that the adhesive layer is destroyed when the laminated steel plate 1 is processed, or that delamination is easily initiated starting with the adhesive layer. In addition, the adhesive storage module G 'can be evaluated by the highest value of the adhesive storage module measured at frequencies of 0.1 Hz to 10 Hz. An adhesive film that is crosslinked and cured by adding the same story thermally that a state of lamination in the case of a thermosetting adhesive, or an adhesive film in the case of a thermoplastic adhesive, can be measured through a publicly known dynamic viscosity measuring device.

In addition, a ratio as 6 (= G '' / G ') between a module G' 'of loss at the above-mentioned temperature of

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the adhesive layer and the storage module G 'is preferably as 6 <1, more preferably as 6 <0.8, even more preferably as 6 <0.5, still more preferably as 6 <0.1. The smaller it is so 6, the more progressive deformation of the adhesive layer is suppressed due to residual stresses when heated and the shape can be stable. On the other hand, as much as> 1, the adhesive layer can flow viscously when the product heats up to the aforementioned temperature and causes an unstable form, or it can produce progressive deformation and destruction and thus cause delamination.

Examples of the adhesive that can be used for the adhesive layer include resin-based thermosetting adhesives such as urea resin, melanin resin, phenol resin, resorcinol resin, epoxy resin, polyester base, polyurethane base, polyamide base , polybenzimidazole base, acrylate base, and the like, thermoplastic adhesives based on vinyl acetate resin base, polyvinyl acetal base, ethylene vinyl acetate based resin base, vinyl chloride base, acrylics, base of acrylate resin, polyamide base, cellulose base, polyester base, polyolefin base, and the like, natural asphalt adhesives, natural rubber, protema, starch, and the like, nitrile rubber elastomer based adhesive, rubber based in styrene, polysulfide base, butyl rubber base, silicon rubber base, acrylic rubber base, modified silicon rubber base, urethane rubber base, silylation urethane rubber base, and the like ares, inorganic adhesives such as Y-glycidoxypropyltrimethoxylan silane coupling agent or p - (3, 4-epoxycyclohexyl) ethyltrimethoxylan, and the like and titanium coupling agent, and the like which may be selected in correspondence with the resin sheet 13. When the resin sheet 13 is a polyamide-based resin or polyurethane-based resin, based on polyister, polyamide-based adhesives are preferred because of its affinity with both the resin sheet 13 and the steel plate 5 of surface layer (or group 11 of grid threads). In addition, due to the heat resistance of the adhesive, a heat fusion reactive adhesive obtained by adding a crosslinking agent to such adhesive base materials is preferred. Among others, a polyester-based reactive thermopreg adhesive obtained by adding a crosslinking agent to a polyester-based adhesive base material is particularly preferred with respect to handling ability.

An example of the polyester base material that can be used for the reactive thermo impregnated adhesive is saturated polyester formed of a diol residue and a dicarboxylic acid residue, which are exemplified above. Among others, a copolymer polyester formed of several diol residues or several dicarboxylic acid residues or a combination thereof is preferred because it reduces the degree of crystallization and improves the adhesiveness. Specifically, a polyester is preferred in which, with main components of 1,4-butadiol and a terephthalic acid residue, other diol residues or dicarboxylic acid residues are copolymerized. More specific examples include "Vylon" manufactured by Toyobo, "Hardec" manufactured by Asahi Kasei, "KEMIT" manufactured by Toray, "Aron Melt PES" manufactured by Toagosei, "Polyester" manufactured by Nippon Synthetic Chemical Industry, and the like. Crystal types are preferred to amorphous types in view of their heat resistance.

Examples of the crosslinking agent that can be used for the reactive thermopreg adhesive include imidazole, isocyanate, epoxy resin, phenolic novolac chemical compound, melanin compound, and the like. Among others, an isocyanate chemical compound is particularly preferred due to the controllability of the crosslinking reaction rate. The isocyanate chemical compound is an aromatic or aliphatic series isocyanate chemical compound having two or more isocyanate functional groups and a mixture thereof. Specifically, there are aromatic series isocyanate chemical compounds such as diphenylmethane diisocyanate compound (MDI), modified carbodiimide MDI, diphenylmethane 4,4-diisocyanate, diphenylmethane-2,2'-diisocyanate, diphenylmethane-2, 4'-diisocyanate, the oligomer phenylmethylene isocyanate (TDI), tetramethyl xylene diisocyanate (TMXDI), naphthylene diisocyanate, triphenylmethane triisocyanate, and the like, aliphatic series diisocyanates such as isophoronediisocyanate diisocyanate aliphatic diisocyanate, aliphatic dihydrate, aliphatic dihydrate dihydrate , allyclic polyisocyanate, and the like, and triisocyanate, and polyisocyanate.

(Union of grid wire group and surface layer steel plate)

Next, as the group 11 of grid wires and the surface layer steel plate 5 can be joined directly in this embodiment, the union of the group 11 of grid wires and the surface layer steel plate 5 in this embodiment will be described. . First, the preferred adhesion between the group 11 of grid threads and the surface layer steel plate 5 can be evaluated by the resistance to separation. The group 11 of grid wires and the surface layer steel plate 5 of this embodiment preferably join with the separation resistance of 5 N / cm or greater. When the separation resistance is less than 5 N / cm, the surface layer steel plates 5 on both sides of the core layer 10 become a body and do not deform during bending deformation or tensile deformation of the laminated steel plate 1, and it may occur that the laminated steel plate 1 does not have stiffness and shock resistance. In order to make a displacement of the surface layer steel plates of both faces of the core layer 10 by shear during a bending deformation of the laminated steel plate 1 is small, the separation resistance is preferably 25 N / cm or greater, more preferably 40 N / cm or greater, even more preferably 60 N / cm or greater. In addition, the separation resistance can be evaluated by the JIS Z0238 T-separation test.

In the case where the group 11 of grid wires is a wire grid formed of steel wires, a method of joining steel materials known publicly to the method of joining group 11 of wire wires can be applied

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Grid and plate 5 steel surface coating. Specifically, for example, bonding, bonding, welding, or the like can be used.

When the group 11 of grid threads and the surface layer steel plate 5 are bonded together, an adhesive is used as the bonding material. At this time, in order to retain the heat-resistant stability after processing, a G 'module of adhesive storage at 100 ° C to 160 ° C is preferably 0.05 MPa or greater and 100 GPa or less. As described above, when the laminated steel plate 1 is formed, residual stresses occur at the interface between the surface layer steel plate 5 (or the group 11 of grid wires) and the adhesive. When a shaped product of the rolled steel plate 1 is heated to the aforementioned temperature (100 ° C to 160 ° C), if the adhesive storage module G 'is less than 0.05 MPa, the adhesive layer is deforms progressively due to these residual stresses, which can cause the destruction of the adhesive layer or a delamination principle from the adhesive layer. To avoid progressive deformation of the adhesive layer more safely, the adhesive storage module G 'is more preferably 1.0 MPa or greater, even more preferably 5 MPa or greater. On the other hand, when the G 'storage module of the adhesive is greater than 100 GPa, the G' storage module at room temperature increases, and therefore the processing capacity decreases. Consequently, it can happen that the adhesive layer is destroyed when the laminated steel plate 1 is processed, or delamination occurs easily starting with the adhesive layer. In addition, the adhesive storage module G 'can be evaluated by a larger value of the adhesive storage module measured at frequencies of 0.1 Hz to 10 Hz. An adhesive film crosslinked and cured by adding the same thermal history as A state of lamination in the case of a thermosetting adhesive, or an adhesive film in the case of a thermoplastic adhesive, can be measured by a publicly known dynamic viscosity measuring device.

In addition, a ratio as 6 (= G '' / G ') between a module G' 'of losses at 100 ° C to 160 ° C of the adhesive layer and the storage module G' is preferably as 6 <1, more preferably as 6 <0.8, even more preferably as 6 <0.5, and even more preferably as 6 <0.1. When smaller is so 6, more progressive deformation of the adhesive layer by residual stresses is suppressed when heated and the shape can be stable. On the other hand, when so 6> 1, the adhesive layer can flow viscously when the product is heated at 100 ° C to 160 ° C and cause an unstable shape, or progressive deformation and destruction may occur, and cause delamination.

Specific examples of the adhesive that can be used as a bonding material for the group 11 of grid threads and the surface layer steel plate 5 include those similar to the previously described adhesives used to bond the resin sheet 13 and the steel plate 5 of surface layer or group 11 of grid threads.

When the group 11 of grid wires and the surface layer steel plate 5 are joined by a brazed joint, a brazing agent is used as the bonding material. Examples of brazing material that can be used at this time include soft solder alloys formed by an alloy of lead, tin, antimony, cadmium, zinc and / or the like, hard solder alloys such as Ni-Cr based welding agent, copper solder alloys, gold solder alloys, palladium solder alloys, silver solder alloys, aluminum solder alloys, and the like.

When the group 11 of grid wires and the surface layer steel plate 5 are joined by welding, a publicly known welding method can be used. Specific examples of the welding method include resistant welding such as spot welding, continuous welding, and the like, electron beam welding, laser welding, arc welding, and the like.

Furthermore, when the group 11 of grid wires is a wire grid formed of steel wires, it is necessary to maintain an initial metal structure of steel wires, in order to retain the strength of the steel wires. From that point of view, the bonding temperature when the group 11 of grid wires and the surface layer steel plate 5 is joined is preferably 400 ° C or less so that there is no phase transformation of the structure of steel, more preferably 300 ° C or less, even more preferably 200 ° C or less, even more preferably 100 ° C or less. Furthermore, if it is possible to join the group 11 of grid threads and the plate 5 and surface layer steel below 100 ° C, deterioration by aging of the surface layer steel plate 5 can be prevented, and a Intense processing

(Thickness of rolled steel plate)

The thickness of the laminated steel plate 1 according to this invention is not particularly limited, and can be modified as appropriate according to the desired features. For example, when it is desired to give priority to stiffness and shock resistance as characteristic of the laminated steel plate 1, the thickness of the laminated steel plate 1 can be determined with the expression (3) or the expression (4) previously described or similar depending on the structure (thread diameter, opening, elastic limit, and the like) of the group 11 of selected grid threads.

The total thickness and a structural thickness ratio (thickness ratio between the surface layer steel plate 5 and

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The core layer 10) of the rolled steel plate 1 according to this embodiment is not particularly limited and can be determined based on a balance between the thickness and stiffness D of the surface layer steel plate 5 and lightness. Specifically, the necessary thicknesses of the core layer 10 and the surface layer steel plate 5 can be determined from the desired stiffness and plate density (specific gravity of steel plate) according to the following expressions (5 ) to (7).

D = 1/3 [(E1 - E2) (y1 - ye) 3 + (E2 - Ea) (y2 - ye) 3 + E-, ye3 + E3 (h - ye) 3] ... (5)

Ye = [e1 - E2] y12 + (E2 - E3) y22 + E3h2] / [2 ((E1 - E2) y1 + (E2 - E3) y2 + E3h)] ... (6)

p = [7.8 (h - y2 + y1) + core layer (y2 - y1)] / h ... (7)

(In the expressions (5) to (7) above, E1 is Young's modulus of the surface layer steel plate 5A on the side of the lower face, E2 is Young's modulus of the core layer 10, E3 is Young's module of the surface layer steel plate 5B on the side of the upper face, and 1 is the thickness of the surface layer steel plate 5, and 2 is y1 + the thickness of the core layer 10, and it is the coordinate and of a neutral axis, h is y2 + thickness of the surface layer steel plate 5A on the side of the upper face, and the core layer is the density of the core layer).

In addition, a preferred thickness of the surface layer steel plate 5 is 0.2 mm to 2.0 mm, and a thickness

Preferred core layer 10 is 0.1 mm to 3.0 mm. When the thickness of the layer 5 steel plate

surface is less than 0.2 mm, surface undulation can easily occur during bending. On the other hand, when the thickness of the surface layer steel plate 5 is greater than 2.0 mm, it is easy for the weight reduction effect to become insufficient. From a weight reduction point of view, the thickness of the surface layer steel plate 5 is more preferably 1.0 mm or less. On the other hand, when the thickness of the core layer 10 is less than 0.1 mm, the total thickness of the laminated steel plate 1 cannot be obtained, and therefore it can be difficult to increase the stiffness at the same time as Maintains lightness. Furthermore, when the thickness of the core layer 10 is greater than 3.0 mm, the thickness of the laminated steel plate 1 itself increases, and therefore the bending stresses applied to the surface layer steel plate 5 increase and It is easy to produce superficial undulation of the steel plates.

Furthermore, in the laminated steel plate 1 according to this embodiment, the core layer 10 can be laminated between the surface layer steel plates 5 with a different thickness. Therefore, the thick surface layer steel plate can be established as a portion with a large radius of curvature to be processed,

to improve its manageability. In addition, when the surface layer steel plate 5, the group 11 of threads of

grid, and the resin sheet 13 are joined together with an adhesive, the thickness of the adhesive layer is not

particularly limited because sufficient heat resistance and durability can be provided to the layer

adhesive when the G 'storage module is 0.05 MPa or greater and 100 GPa or less over the entire temperature range from 100 ° C to 160 ° C, even if the thickness becomes small. However, from an economic efficiency point of view, the thickness of the adhesive layer is preferably 30 pm or less. Also, to sufficiently show the effect of the adhesive layer, the thickness of the adhesive layer is more preferably 1 pm or greater.

(Manufacturing method of rolled steel plate)

Next, a method of manufacturing the rolled steel plate 1 having the structure described above will be described in detail.

The rolled steel plate 1 according to this embodiment can be manufactured by applying a publicly known steel plate rolling method. Specifically, it can be manufactured by the following processes, or the like.

(1) Steel wires having a carbon content of 0.24% by mass or more are used to make the group 11 of grid wires.

(2) A bonding material (adhesive, brazing agent, or the like) is applied as required on both sides of the core layer 10 (one or more groups 11 of grid wires, one or more sheets 13 of resin) . Then, when it is intended to form the core layer 10 having the structure illustrated in Figure 1 for example, the surface layer steel plate 5A, the resin laminate 13, the grid wire group 11, the laminate are laminated 13 of resin, the group 11 of grid wires, the sheet 13 of resin, and the plate 5B of surface layer steel in this order, and are compressed at room temperature or while heating.

In addition, the structure of the core layer 10 is not limited to the example illustrated in Figure 1, and may have a portion where groups 11 of grid wires or resin sheets 13 are laminated sequentially. In addition, in the process of (2), the core layer 10 and the surface layer steel plates 5A, 5B can be joined directly without using the adhesive. In addition, specific examples of the joining material and the joining method are as described above.

[Second embodiment]

Next, the overall structure of the rolled steel plate according to a second one will be described

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Embodiment of the present invention with reference to Figure 6. Figure 6 is a cross-sectional view illustrating an example of the overall structure of a plate 2 of rolled steel according to this embodiment.

As illustrated in Figure 6, the rolled steel plate 2 according to this embodiment has a structure in which the surface layer steel plates 5 (5A, 5B) are laminated respectively on both sides of the core layer 10 , similar to the laminated steel plate 1 according to the first embodiment. That is, the laminated steel plate 2 has a structure in which the core layer 10 is laminated on the surface layer steel plate 5A, and the surface layer steel plate 5B is laminated thereon. In a manner similar to the first embodiment, the core layer 10 is a layer formed by one or more groups 11 of grid-shaped grid threads using threads and one or more sheets of resin 13 where a base material is formed of resin in the form of a sheet. However, as illustrated in Figure 6, the rolled steel plate 2 according to this embodiment differs from the first embodiment in that the grid wire groups 11 are located near the sides of the layer steel plate 5 superficial.

Although Figure 6 illustrates an example in which the groups 11 of grid threads are attached directly to the surface layer steel plates 5, it is not always necessary to directly connect the groups 11 of grid wire and the steel plates 5 of surface layer. A resin sheet thinner than the laminated resin sheet 13 between the two groups 11 of grid wires can be laminated between the surface layer steel plates 5 and the groups 11 of grid wires, and the groups 11 of grid wires they can be placed near the sides of the surface layer steel plates 5 throughout the core layer 10. From the point of view of improving damping performance, adhesion and corrosion resistance, which are effects of the groups 11 of grid threads by the resin sheets 13 described above, it is quite preferred that the most superficial layer of The core layer 10 in contact with the surface layer steel plate 5 is made of the resin sheet 13.

Furthermore, although Figure 6 illustrates an example in which the two groups 11 of grid threads are respectively located near the sides of the surface layer steel plates 5A, 5B, it is not necessary that each of the groups 11 of grid threads are located near the sides of the plates 5A, 5B surface layer steel. Two or more groups 11 of grid wires can be laminated on one or both plates 5A, 5B of surface layer steel. This case also includes the case in which the resin sheet 13 is laminated between groups 11 of adjacent grid wires.

By means of groups 11 of grid wires asf located near the sides of the surface layer steel plates 5 in the core layer 10, the distance between the neutral axis and the group 11 of grid wires when the steel plate 2 Laminate is processed grows, and the stiffness and shock resistance of laminated steel plate 2 can be improved more efficiently. Therefore, as steel plates for applications where stiffness and shock resistance are particularly demanded, it is preferable to use the rolled steel plate 2 according to this embodiment.

In addition, the other structure and manufacturing method of the laminated steel plate 2 are similar to those of the first embodiment described above, and therefore detailed descriptions thereof are issued.

[Third embodiment]

Next, the overall structure of a rolled steel plate according to a third embodiment of the present invention will be described with reference to Figure 7. Figure 7 is a cross-sectional view illustrating an example of the overall structure of a rolled steel plate 3 according to this embodiment.

As illustrated in Figure 7, the laminated steel plate 3 according to this embodiment has a structure in which surface layer steel plates 5 (5A, 5B) are laminated respectively on both sides of the core layer 10 , in a manner similar to the laminated steel plate 1 according to the first embodiment. That is, the laminated steel plate 3 has a structure in which the core layer 10 is laminated on the surface layer steel plate 5A, and the surface layer steel plate 5B is laminated thereon. Similar to the first embodiment, the core layer 10 is a layer formed by one or more groups 11 of grid wires formed in a grid shape using threads and one or more resin sheets 13 where a resin base material is formed with A form of laminate. However, as illustrated in Figure 7, the laminated steel plate 3 according to this embodiment differs from the first embodiment in that the groups 11 of grid threads are placed at the bias on a central portion side in the direction of the core layer 10 thickness.

Although Figure 7 illustrates an example in which two groups 11 of grid wires are attached directly near the center portion in the direction of the thickness of the core layer 10, it is not always necessary to directly join the two groups 11 of wires of grid. A resin sheet thinner than the laminated resin sheet 13 between the two groups 11 of grid wires and the surface layer steel plate 5 (5A, 5B) can be laminated between the two groups 11 of grid wires, and the two groups 11 of grid wires can be positioned at the bias on the side of the central portion in the direction of the thickness of the core layer 10 throughout the core layer 10.

In addition, although Figure 7 illustrates an example in which the two groups 11 of grid wires are placed at the bias in the

5

10

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twenty

25

30

35

40

Four. Five

fifty

55

60

65

side of the central portion in the direction of the thickness of the core layer 10, there is no need to be two groups 11 of grid wires located on the side of the central portion in the direction of the thickness of the core layer 10. Three or more groups 11 of grid wires can be laminated on the side of the central portion in the direction of the thickness of the core layer 10. This case includes the case in which the resin sheet 13 is laminated between groups 11 of adjacent grid wires.

Thus, by means of the groups 11 of grid wires located at the bias on the side of the central portion in the direction of the thickness of the core layer 10, the neutral axis is no longer displaced by the shear deformation in the layer 10 of nucleus even when it curves and deforms. On the other hand, in the first and second embodiments described above, the central portion of the core layer 10 is not sufficiently reinforced by means of the group 11 of grid wires, and therefore the neutral axis moves into the bending when it bends and deforms during the shear deformation of the core layer 10, and the radius of curvature increases. At this point, on the rolled steel plate 3 according to this embodiment, it is possible that compression deformation and tensile deformation may appear, and the stresses can be dispersed along a wide surface compared to plates 1, 2 of rolled steel according to the first and second embodiments. Therefore, it is possible to improve the ductility of the rolled steel plate 3 using the core layer 10 according to this embodiment. Therefore, for steel plates in applications where ductility is particularly important, preferably the rolled steel plate 3 of this embodiment is used.

Here, the effect of improving ductility by means of the rolled steel plate 3 according to this embodiment will be described in detail with reference to Figure 8A and Figure 8B. Figure 8A and Figure 8B are examples of views illustrating an example of a difference in bending deformation behavior between the rolled steel plate according to the first embodiment and the rolled steel plate according to this embodiment of the present invention. Figure 8A illustrates a bending deformation behavior of the rolled steel plate according to the first embodiment, and Figure 8B illustrates a bending deformation behavior of the rolled steel plate according to the third embodiment.

First, as illustrated in Figure 8A, for example, when the rolled steel plate 1 according to the first embodiment is curved using a roller R, the group 11 of grid threads with a greater elastic limit than the sheet Resin 13 is in a position relatively close to the surface layer steel plate 5. Accordingly, the neutral C axis moves inward (roller R side) instead of the central portion in the direction of the thickness of the rolled steel plate 1 during bending deformation, and therefore the radius of curvature is made big. Furthermore, when the rolled steel plate 1 bends and deforms, a portion 1a where the tensile stresses are large and a portion 1b where the compression stresses are large are concentrated on a narrow surface. Therefore, the fracture deflection of the rolled steel plate 1 is relatively small, and the ductility may become slightly insufficient in applications where ductility in particular, or the like is necessary.

On the other hand, as illustrated in Figure 8B, for example, when the rolled steel plate 3 according to this embodiment is curved using the roller R, the group 11 of grid threads having a greater elastic limit than the sheet Resin 13 is located in a position away from the surface layer steel plate 5. Consequently, the neutral C axis does not travel further inward (roller side R) than the central portion in the direction of the thickness of the rolled steel plate 1 during bending deformation, and the radius of curvature can be made small. Furthermore, when the rolled steel plate 3 is curved and deformed, a portion 3a where the tensile stresses are large and a portion 3b where the compression stresses are large can be dispersed over a wide surface. Therefore, in the laminated steel plate 3 in which the groups 11 of grid wires are located bias in the central portion in the direction of the thickness of the core layer 10, the fracture deviation can be increased, and the fracture can be improved, and can be improved Ductility more than laminated steel plate 1.

In addition, the other structure and manufacturing method of the rolled steel plate 3 are similar to those of the first embodiment described above, and therefore detailed descriptions are omitted.

[Summary]

The rolled steel plates according to the first and third embodiments of the present invention described are light, very sharp and resistant to shocks, and have excellent heat-resistant handling and stability after being processed, even when subjected to intense processing such as curving, deep drawing, or the like. In addition, in the laminated steel plates according to the previously described embodiments, the core layer 10 has the resin sheet 13 in addition to the group 11 of grid threads, and thereby the damping performance can be improved. Therefore, rolled steel plates according to the first to third embodiments of the present invention can be used as members for automobiles, appliances, furniture, office automation devices, and the like, and can preferably be used as steel plates particularly for parts of laminates that are painted after being shaped through intense processing such as drawing, bending, profiling, or the like.

EXAMPLE

Hereinafter, the present invention will be described more specifically using examples.

(Steel plates, grid wire groups, and grid sheets used)

In this example and the comparative examples, the surface layer steel plates illustrated in Table 1, the wire racks (groups of grid threads) illustrated in Table 2, and the resin sheets illustrated In Table 1, they were used to make rolled steel plates. Here, the PET-based alloys in Table 3 are an alloy with a PET (RN163 manufactured by Toyobo) / ionomer (Himilan 1706 manufactured by Mitsui DuPont) / ethylene-based rubber ratio (EBM2401P manufactured by JSR) of 80 parts in mass / 10 parts in mass / 10 parts in mass. In addition, for the foams (foam sheets) used in this example and the comparative examples illustrated in Table 3, a PET-based alloy and a nylon sheet were impregnated with super-quantum CO2 at 20 MPa and 32 ° C, below. the pressure was released, and they were transformed into foam by heating to 260 ° C, 240 ° C respectively. Then, after heating, they cooled to 0 ° C to stop the growth of bubbles, thus obtaining the foam sheets illustrated in Table 3. In addition, by adjusting the impregnation time of super-quantum CO2, the time of heating and cooling time, the foam ratios and bubble diameters of the foam sheets were controlled. In addition, the "single interlaced + 45 °" of the "interlaced" column of Table 2 denotes a case where oblique threads are interwoven according to a direction that forms 45 ° with respect to the directions of the vertical threads and the horizontal threads to obtain a grid of threads with simple interlacing.

[Table 1]

Table 1. Structure of the surface layer steel plate

 Surface Layer Steel Plate

 Coating Thickness (mm) Tensile strength (MPa)

 one

 GI 0.27 340

 2

 TFS 0.22 400

 3

 GA 0.8 270

 4

 SUS304 0.8 630

 5

 GA 1 1000

twenty

[Table 2]

Table 2. Structure of the wire rack

 Core layer wire grid

 Interlaced Steel Cable

 Thread Diameter (Mm)

 [C] x 10-2% mass Tensile strength MPa Opening * (Mm) Thickness (Mm) Opening rate (%) Plate density (g / cm2) Interlaced

 one

 500 26 1000 2176 1000 66 0.2652 Simple interlaced

 2

 300 75 2700 700 600 77 0.10764 Simple interlaced

 3

 25 60 3000 85 50 60 0.0156 Simple interlaced

 4

 100 75 2700 700 200 70 0.0468 Simple interlaced + 45 °

 5

 100 75 2700 700 200 77 0.03588 Simple Wavy Interlacing

 6

 100 75 2700 700 200 77 0.03588 Flat top

 7

 500 26 1000 300 1500 1000 41 0.27612 Ton-cap display

 8

 500 26 1000 1500 1000 45 0.2145 Hexagonal wire rack

 9

 25 60 3000 20 50 20 0.0312 Simple interlaced

 10

 500 20 600 2176 1000 66 0.2652 Simple interlaced

 eleven

 500 26 3000 10000 1000 90 0.078 Simple interlaced

[Table 3]

Table 3. Structure of the resin sheet

 Resin sheet

 Resin base material Expansion ratio Average bubble diameter (pm) Distance between more adjacent bubbles (pm)

 one

 PET based alloy None

 2

 PET based alloy Twice 1 0.5

 3

 Nylon-6 Twice 1.5 1

 4

 PP Twice 1.5 1

(Manufacture of resin wire mesh grids)

Subsequently, wire grids embedded in resins were obtained, where the wire grids illustrated in Table 5 2 were embedded in the resin sheets illustrated in Table 3. Specifically, first, an adhesive

illustrated in Table 4 below, it was spread on a side of a resin sheet 0.55 times the thickness of the wire gratings. Next, the resin sheet was laminated on both sides of the wire racks so that the face of the resin on which the adhesive was extended came into contact with the wire rack, joining by pressure at a predetermined temperature (260 ° C when the resin sheet was alloy 10 based on PET or 240 ° C when the resin sheet was nylon) and a predetermined pressure (10 kgf / cm2 up to 40 kgf / cm2 (0.98 MPa up to 2.92 MPa)), thus obtaining the wire gratings No. 1 up to 15 embedded in resin as illustrated in Table 4 below. In addition, between the wire gratings No. 1 to 15 embedded in resin, for those in which several wire gratings were used, first, wire gratings embedded in resin were made, where a wire rack was embedded in a sheet of resin as described above. Next, the adhesive was spread on surfaces of the wire grids obtained embedded in resin, and the wire grids embedded in resin were laminated so that the respective adhesive coated faces of the wire grids embedded in resin come into contact. with each other, they were then heated and joined together under pressure, thus obtaining wire grids embedded in resin with several laminated wire grids (N ° 3 to N ° 6, N ° 9, N ° 12) with several laminated wire grids.

twenty

[Table 4]

Table 4. Wire gratings embedded in resin

 Grids of resin embedded threads

 Grid of threads Resin laminate Grid of threads embedded in resin

 Wire rack

 Number of wire grates Thickness (mm) Plate density (g / cm2) Laminate Plate density (g / cm2) Thickness (mm) Plate density (g / cm2)

 one

 one

 one

 one

 0.27 2 0.06 1.07 0.3

 2

 2

 1 0.6 0.11 2 0.04 0.642 0.1

 3

 3

 10 0.5 0.16 2 0.03 0.535 0.2

 4

 4

 5 1 0.18 2 0.06 1.07 0.2

 5

 5

 5

 1 0.18 2 0.06 1.07 0.2

 6

 6

 5 1 0.18 2 0.06 1.07 0.2

 7

 7

 1 1 0.28 2 0.06 1.07 0.3

 8

 8

 1 1 0.21 2 0.06 1.07 0.3

 9

 9

 10 0.5 0.31 2 0.03 0.535 0.3

 10

 1 1 1 0.27 1 0.14 1.07 0.4

 eleven

 1 1 1 0.27 3 0.06 1.07 0.3

 12

 3 10 rolled at each rotation of 36 ° 0.5 0.16 2 0.03 0.535 0.2

 13

 10 1 1 0.27 2 0.06 1.07 0.3

 14

 11 1 1 0.08 2 0.06 1.07 0.1

 fifteen

 1 1 1 0.27 4 0.05 0.04 0.3

 16

 3 10 0.5 0.16 2 0.10 2.15 0.3

 17

 3 10 0.5 0.16 2 0.10 2.15 0.3

 18

 3 10 0.5 0.16 2 0.10 2.15 0.3

 19

 4.5 Central of 5 upper and lower: six of 3 0.5 0.13 2 0.10 2.15 0.3

5

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40

In addition, in addition to the wire gratings No. 1 to No. 15 embedded in resin, a PET-based alloy foam sheet having a thickness of 150 pm and a wire rack were repeatedly laminated in this order for ten layers. In addition, the PET-based alloy foam sheet having a thickness of 150 pm was laminated on the upper face (the uppermost face), and was subjected to thermocompression under the conditions described above, thus obtaining the wire grid No. 16 embedded in resin illustrated in Table 4. In the wire rack No. 16 embedded in resin in this way, the wire racks were uniformly arranged in the core layer resin.

In addition, in addition to the wire gratings No. 1 to No. 15 embedded in resin, five wire gratings were laminated on each of both sides of a PET-based alloy foam sheet each of which has a thickness of 1350 pm with the adhesive illustrated in Table 5 extended on both sides. Then, a PET-based alloy having a thickness of 1500 pm was laminated on each wire grid on both sides, and subjected to heat-compression bonding under the conditions described above, thus obtaining the wire mesh No. 17 embedded in resin. illustrated in Table 4. On the wire grid No. 17 embedded in resin in this way, the wire screens were located near the upper and lower surface portions (sides of the surface layer steel plates) of the layer of resin in the core layer.

[Table 5]

Table 5. Composition of the adhesive layer

 Base material Curing agent Base material / curing agent G 'tan 6

 Adhesive 1

 PES314S30 Coronatel 100/5 1 ~ 30 MPa 0.3

 G '(Storage module), so 6 is a dynamic measurement value (10Hz) at 100 ° C to 160 ° C

In addition, in addition to the wire gratings No. 1 to No. 15 embedded in resin, adjacent wire gratings were joined to have ten gratings of rolled yarns. Then, a PET-based alloy foam sheet with a thickness of 1100 pm was laminated on both upper and lower faces of the laminated wire grids, and subjected to heat compression bonding under the conditions described above, obtaining the wire grid No. 18 embedded in resin illustrated in Table 4. In the wire rack No. 18 embedded in resin in this way, the wire racks are arranged bias in the central portion (central side in the direction of the thickness of the layer core) of the resin layer in the core layer.

In addition, in the wire gratings No. 1 to No. 18 embedded in resin, the respective laminated wire gratings or the wire gratings and the resin sheets were bonded using the adhesive illustrated in Table 5.

(Production of rolled steel plate)

As a method of specific production of the laminated steel plate of this example, first, the adhesive illustrated in Table 5 was spread on one side of a 300 mm x 300 mm steel plate illustrated in Table 1. Next , the steel plate, the wire mesh embedded in the resin, and the steel plate were laminated in this order with the adhesive in contact with the wire mesh embedded in resin obtained as described above, thus obtaining a laminated body. Next, it was heated to the predetermined temperature (260 ° C when the resin sheet is PET-based alloy or 240 ° C when the resin sheet is nylon). Then, a wedge with a predetermined thickness was used to surround four faces of the laminated body, and was subjected to thermal compression for two minutes with a compression force of 10 kgf / cm2 to 40 kgf / cm2 (0.98 MPa to 2 , 92 MPa) and then cooled to room temperature, thus obtaining each rolled steel plate of Examples No. 1 through No. 25 illustrated in Table 6.

[Table 6]

Table 6. Structure of rolled steel plate

 Example

 Structure of rolled steel plate

 Surface Layer Steel Plate

 Core layer

 Resin embedded wire rack

 Thickness (mm) Plate density (g / cm2) Total thickness (g / cm2)

 one

 one

 one

 1.07 0.33 1.61

 2

 1 2 0.64 0.15 1,182

 3

 1 3 0.54 0.19 1,075

 4

 1 4 1.07 0.24 1.61

 5

 1 5 1.07 0.24 1.61

 6

 1 6 1.07 0.24 1.61

 7

 1 7 1.07 0.34 1.61

 8

 1 8 1.07 0.28 1.61

 9

 1 9 0.54 0.34 1.075

 10

 1 10 1.07 0.40 1.61

 eleven

 1 11 1.07 0.33 1.61

5

10

fifteen

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25

30

 12

 1 12 0.54 0.19 1.08

 13

 1 4 0.54 0.19 1,075

 14

 2 1 1.07 0.33 1.43

 fifteen

 3 1 1.07 0.33 2.67

 16

 4 1 1.07 0.33 2.67

 17

 5 1 1.07 0.33 3.07

 18

 4.5 1 1.07 0.33 2.87

 19

 1 15 1.07 0.33 1.61

 twenty

 1 1 1.07 0.33 1.61

 twenty-one

 1 12 0.54 0.19 1.08

 22

 1 16 2.15 0.29 2.69

 2. 3

 1 17 2.15 0.29 2.69

 24

 1 18 2.15 0.29 2.69

 25

 1 19 0.54 0.15 1.075

 Comparative Example 1

 1 Wire rack 1 1 0.27 1.54

 Comparative Example 2

 1 Die-cut metal embedded in resin 1.07 0.33 1.61

 Comparative Example 3

 1 13 1.1 0.33 1.64

 Comparative Example 4

 1 14 1.1 0.14 1.64

 Comparative Example 5

 1 Niron glass reinforced 1.28 0.27 1.82

 Comparative Example 6

 1 Alloy based on PET form 1.35 0.27 1.89

 Comparative Example 7

 1 Foam PP 1.07 0.33 1.61

In addition, respective manufacturing methods of a rolled steel plate in the comparative examples are as follows.

(Comparative example 1)

After the adhesive illustrated in Table 3 was spread on both sides of the wire grid No. 1 illustrated in Table 2, the surface layer steel plate No. 1 illustrated in Table 1 was laminated on both sides of this wire grid, and were subjected to thermocompression bonding under the same conditions as example 1 illustrated in Table 6, thus obtaining the rolled steel plate of comparative example No. 1.

(Comparative example 2)

First, a steel plate with a plate thickness of 2.1 mm and a tensile strength of 980 MPa was punched to form circular holes with a diameter of 2.0 mm (opening rate 66%). Next, the plate processed after being die cut was embedded in a PET-based alloy foam sheet similar to the wire mesh No. 1 embedded in resin illustrated in Table 5. Next, the rolled steel plate was obtained. from comparative example No. 2 where a processed plate embedded in the resin was a core layer under the same conditions as example No. 1.

(Comparative examples 3 to 4)

A rolled steel plate of comparative example No. 3 was obtained where the wire grid No. 10 with the lowest carbon content was embedded by the same procedure as Example No. 1. In addition, a rolled steel plate of the comparative example No. 4 where the wire grid No. 11 was embedded with the largest opening by the same procedure as example No. 1.

(Comparative examples 5 to 6)

A nylon sheet containing glass fibers (with a thickness of 1.5 mm, a glass fiber content of 30% by mass, and a tensile strength of 34 MPa) was laminated between plates 1 of layer steel surface in a manner similar to example No. 1, thus obtaining the laminated steel plate of comparative example 5. In addition, a PET-based alloy foam sheet was laminated between the surface layer steel plates 1 in a manner similar to example 1, thus obtaining the rolled steel plate of comparative example 6.

5

10

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25

30

35

40

Four. Five

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55

60

65

(Comparative example 7)

A PP foam sheet with a thickness of 1 mm was used as the core layer, and an acid modified PP with a thickness of 0.05 mm was used as an adhesive, thus obtaining the rolled steel plate of comparative example 7 by the same procedure as example 1.

(Physical properties, processing performance / damping test of rolled steel plates)

From each rolled steel plate of the examples obtained as described, a test piece (25 mm x 150 mm) was cut in accordance with ASTM D-790, and a distance between 50 mm pivot points was established and established a speed of 5 mm / min, to carry out a three-point bend test. At this time, in examples N ° 1 to N ° 19, and N ° 22 to N ° 24, the test piece is cut so that the longitudinal direction and the width direction of the test piece correspond to the direction of the tetragonal meshes of the wire mesh of the lower layer. In addition, in examples No. 20 and No. 21, the test piece was cut so that the longitudinal direction and the width direction of the test piece correspond to the direction of the diagonal lines of the tetragonal meshes of the wire rack of the lowermost layer.

Then, from each test piece, the measured distortion - gradient 6 of the load curve (calculated using a load of up to 1/3 of the maximum load) was replaced in expression (i) to calculate the stiffness D a the flexion In addition, the bending moment of the plastic region of the rolled steel plate was calculated using the expression (ii). Furthermore, as it is known that the impact resistance of a steel plate has a correlation with the moment of curvature of a plastic region, the moment of curvature of the plastic region calculated by means of the expression (ii) was used as an index of shock resistance.

 6 = Pel3 / 48D

 ■■■ (i)

 M = Pl / 4b

 ... (ii)

Aqm, in the expression (i) above and expression (ii), Pe is the measured value, P is the maximum measured curve load, 6 is the magnitude of the distortion, l is the distance between pivot points, and b is The width of the test piece.

In addition, a 125 mm x 30 mm test piece was cut from the rolled steel plate of each example, and a U-shaped bending test piece was made using a square deep drawing test machine (r = 100 mm, BHF (Blank Holder Force): 2 tons) of 20T Universal Test Machine manufactured by Erichsen.

In addition, a test piece (25 mm x 150 mm) of the rolled steel plate of Examples No. 1 to No. 24 was cut, and a loss coefficient was measured at a second resonance frequency by a resonance method cantilever in accordance with JIS-G-0602.

(Evaluations)

<1. Lightness Assessment>

The plate density p of each of the rolled steel plates was calculated using the expression (iii).

p = va Pa + vs Ps ... (iii)

Here, in the previous expression (iii), va and vs are volume fractions of a wire grid and a surface layer steel plate, respectively, and pa and Ps are plate densities of the wire grid and the plate of surface layer steel, respectively. In addition, since the thickness of the adhesive layer is thin compared to the thickness of the entire laminated steel plate, the influence thereof is considered negligible.

Also, from the stiffness D obtained with the expression (i), a plate thickness tp of a single surface layer steel plate necessary to present the same flexural stiffness as that of the rolled steel plate was calculated using the expression (iv), and a mass Wp was obtained for this area unit using the expression (v). Lightness was evaluated when the flexural stiffness is constant using a ratio (W / Wp) between the mass W per unit area of the rolled steel plate and the mass Wp per unit area of the steel plate of the expression (v).

tp = 12D / E ... (iv)

Wp = Pstp ... (v)

Aqm, in the previous expressions (iv) and (v), Es is Young's modulus of the surface layer steel plate (180 GPa in this example), and Wp is the mass per unit area of the steel plate It has the same stiffness as the rolled steel plate.

<2. Assessments of flexural stiffness and shock resistance>

The stiffness Dp of a single steel plate having the same mass as the mass W per unit area of the laminated steel plate calculated with the expression (v) was calculated with the expression (vi). In addition, a relationship (D / Dp) between the stiffness Dp obtained with the expression (vi) and the stiffness D of the rolled steel plate was calculated, and the stiffness of the rolled steel plate was evaluated. Aqm, when D / Dp> 1, it was evaluated that the stiffness has been reasonably increased compared to the case of the single steel plate.

Dp = En / 12 (p / ps) 3 ... (vi)

10 Similarly to the evaluation of the flexural stiffness, the bending moment Mp of the single steel plate of the mass was calculated by the same area unit using the expression (vii) in a manner similar to the evaluation of the stiffness to bending, and the magnitude of the shock resistance with a ratio (M / Mp) between this moment of bending Mp of the single steel plate and the moment of bending M of the plastic region of the steel plate was evaluated laminate obtained with the expression (ii). Here, when M / Mp> 1, it was evaluated that the shock resistance had increased reasonably compared to the case of the single steel plate.

Mp = Ts / 4 (p / ps) 2 ... (vii)

Aqm, in the previous expression (vii), P is the highest bending load, Ts is the tensile strength of a surface layer steel plate 20, l is the distance between pivot points, and b is the width of the test piece Also, when Ts differs between the surface layer steel plates of the upper and lower faces of the core layer, the average Ts values of the surface layer steel plates of the upper and lower faces were used as the resistance to the traction of the surface layer steel plates.

25 <3. Ductility Evaluation>

The bending of the rolled steel plates of examples N ° 22 to N ° 24 continued until the fracture, the magnitude of the deviation at the time of the fracture was measured, and the ductility of the rolled steel plates was evaluated using the measured deviation quantities. Here, it was evaluated that the greater the magnitude of the deviation, the greater the ductility. In addition, the deviation magnitudes were measured with a movement distance of 30 load points.

<4. Evaluation of the validity of the process>

A cross-section of a curved test U-piece was observed visually and with a stereoscopic microscope, and the presence / absence of delamination of the surface layer steel plate, the destruction or surface undulation of the steel plate was examined. of superficial layer and the collapse towards the nucleus layer, the damages in the nucleus layer, and the presence / absence of superficial undulation. Here, it was evaluated that the validity of the process is excellent when there are no abnormalities in any of the sections. In addition, the processed part was placed in an oven heated to 180 ° C, retained for 30 minutes, and then removed from the oven and cooled to room temperature. Then, after processing, the validity of the heated form 40 such as delamination of the surface layer steel plate, the destruction of the core layer, the flow, and the like was evaluated. Here, it was evaluated that the validity of the heated form was excellent when there was no abnormality in any of the sections.

<5. Damping Performance Evaluation>

Based on the loss coefficient at a second resonant frequency measured as described above, the damping performance of the rolled steel plates of Examples No. 1 to No. 24 was evaluated. Aqm, it was evaluated that when the higher the loss coefficient, more favorable was the damping performance.

50 (Evaluation results)

The results of the previous evaluation are illustrated in Table 7 below.

[Table 7]

Table 7. Results of the evaluation of characteristics

 Example

 Characteristics evaluation results Process validity / heat resistance / damping form stability

 Plate mass

 Rigidity Shock resistance Fracture deviation (mm) U-bend processing Heat resistance at 180 ° C Loss factor

 W (g / cm2)

 W / WP D (Nmm2) D / Dp M M / Mp

 one

 0.75 0.60 60614.5 4.56 208.57 2.66 O O 0.98

 2

 0.57 0.60 26458.8 4.60 140.83 3.14 O O 0.96

 3

 0.61 0.70 20881.3 2.93 139.00 2.69 O O 0.92

 4

 0.66 0.54 58035.8 6.28 275.84 4.48 O O 0.95

 5

 0.66 0.54 59603.8 6.45 288.72 4.69 O O 0.95

 6

 0.66 0.54 59603.8 6.45 248.79 4.04 O O 0.98

 7

 0.76 0.60 62911.5 4.53 248.79 3.08 O O 0.98

 8

 0.70 0.56 62543.9 5.80 387.89 5.69 O O 0.98

 9

 0.76 0.86 22157.5 1.57 117.18 1.43 OR 0.98

 10

 0.82 0.66 60614.5 3.44 208.57 2.20 O O 0.6

 eleven

 0.75 0.60 61614.5 4.56 305.89 3.90 OR 0.98

 12

 0.61 0.72 18861.9 2.65 144.28 2.79 OR 0.92

 13

 0.47 0.53 21698.1 6.68 174.36 4.84 O O 0.98

 14

 0.61 0.58 36257.6 5.08 165.66 2.72 OR 0.98

 fifteen

 1.58 0.71 350401.7 2.83 573.75 2.08 O O 0.98

 16

 1.58 0.71 350401.7 2.83 1273.88 1.98 OR 0.98

 17

 1.89 0.73 543457.2 2.55 2739.66 2.34 O O 0.98

 18

 1.73 0.72 440213.6 2.68 1512.27 1.67 O O 0.98

 19

 0.75 0.60 60614.5 4.52 208.57 2.65 O O 0.98

 twenty

 0.75 0.64 50877.3 3.82 170.07 2.17 O O 0.98

 twenty-one

 0.61 0.72 18861.9 2.65 144.28 2.79 OR 0.92

 22

 0.71 0.39 193225.1 17.36 462.15 6.63 20 O O 0.98

 2. 3

 0.71 0.38 208441.4 18.72 982.18 14.10 18 O O 0.98

 24

 0.71 0.40 180473.3 16.21 359.10 5.15 35 O O 0.98

 25

 0.57 0.59 20881 2.93 139 2.69 O O 0.94

 Comparative Example 1

               A * 1 X 0.05

 Comparative Example 2

 0.75 47898.7 3.60 180.26 2.30

 Comparative Example 3

 0.75 63652.6 4.75 156.62 1.99

 Comparative Example 4

               End face crack in surface layer steel plate

 Comparative Example 5

         136.21

 Comparative Example 6

         115.92

 Comparative Example 7

                 X * 2

* 1 occurrence rate of delaminated surface layer steel plate = 2/10 * 2 resin loss on the end face

As illustrated in Table 7, the rolled steel plates of Examples No. 1 to No. 24 met W / Wp <1.0, and it was found that they fear a small plate density compared to a steel plate of the same rigidity and fear excellent lightness. In addition, the rolled steel plates of Examples No. 1 to No. 24 5 met D / Dp> 1.0, M / Mp> 1.0, and were found to have a high flexural rigidity and bending moment in a plastic region compared to one of the same plate density, and therefore have high rigidity and excellent shock resistance.

In addition, the rolled steel plates of Examples No. 1 and No. 21 did not show delamination of the surface layer steel plates, destruction or surface undulation of the surface layer steel plates and collapse towards the core layer, and destruction or surface undulation of the core layer during U-bending or heating after bending, and it was discovered that they were able to remain valid during processing or after post-processing heating.

In addition, the rolled steel plates of Examples No. 1 to No. 24 all had loss coefficients of 0.5 or greater, and were found to fear excellent damping performance.

In addition, it can be speculated that the reason why the stiffness D and the bending moment M of example No. 20 were slightly small compared to example No. 1 is as follows. Example No. 1 has a layer of

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wire grid containing steel wires arranged in parallel with the direction of the width of the surface layer steel plate, while example No. 20 does not fear any steel wire arranged in parallel in the direction of the width of the surface layer steel plate. The steel wires arranged in parallel in the width direction are not deformed by a bending deformation load, and therefore limit the Poisson deformation of the surface layer steel plates. As a result, a bonding force of the surface layer steel plates is produced in the laminated steel plate of example No. 1 containing the steel wires, and therefore in the laminated steel plate of example No. 1, It is conceivable that Young's modulus and the elastic limit increase, and also increase the stiffness D and the M bending moment. On the other hand, in the laminated steel plate of Example No. 2, as the diagonal grid of wire mesh meshes matches the longitudinal direction and the width direction of the curved test piece, it is conceivable that the grid of wires is deformed by shear when the bending load is applied, and there is a displacement between the surface layer steel plates of the upper and lower faces. Therefore, it is conceivable that the stiffness D and the bending moment M become smaller than those of the rolled steel plate of example No. 1.

In addition, the stiffness D and the bending moment M of the rolled steel plate of example No. 12 and the stiffness D and the bending moment M of the rolled steel plate of example No. 21 adopted almost equal values. It is speculated that this is because the wire racks were laminated by modifying the direction of lamination thereof, and became isotropic.

In addition, the laminated steel plate of Example No. 23 had a stiffness D and a bending moment M greater than the laminated steel plate of Example No. 22. Conceivably, this is because the wire gratings of the core layer were located near the sides of the surface layer steel plates, and therefore the distance between the wire racks and the neutral axis was very large, thus increasing the stiffness D and the M moment of bending more efficiently.

In addition, the rolled steel plate of Example No. 24 has a greater fracture deviation than the rolled steel plate of Example No. 22, and also excellent ductility. Conceivably, this is because the wire racks having a high elasticity limit were placed in a central position, and therefore the movement of the neutral axis could be avoided and the radius of curvature became small. Actually, the radius of curvature of the bending test piece of Example No. 24 just before the fracture was obtained by filming the bending deformation with a video camera, and processing the image and calculating the shape of the test piece just before the fracture, and it turned out to be equal to or less than 1/5 of example No. 22.

In addition, the laminated steel plate of Example No. 25 was mostly the same as the laminated steel plate of Example No. 3 in stiffness D, bending moment M, manageability, heat-resistant stability, and damping performance, but fear a lower plate density. It is speculated that this is a consequence of using the wire rack No. 5 with a large opening instead of the wire rack No. 3 in the central portion of the core layer where the contributions of stiffness D and moment M of curved were small, thus increasing the stiffness D and the moment M of bending efficiently and reducing the weight.

In addition, in the laminated steel plate of comparative example No. 1, delamination can occur at the interface between the surface layer steel plates and the wire racks when subjected to U-bending, and was lower than the steel plates Laminates of Examples No. 1 to No. 24 as regards adhesion between the surface layer steel plates and the core layer. In the rolled steel plates of Examples No. 1 to No. 24, as the wire gratings were embedded in the resin sheet, the surface layer steel plates and the core layer were in surface contact. At this point, in the laminated steel plate of comparative example No. 1, the surface layer steel plates and wire grids were in flat contact or point contact, and therefore the contact area was small, which is speculated may be a reason for the aforementioned inferiority. In addition, the loss coefficient of the rolled steel plate of comparative example No. 1 was lower than the loss coefficient of the rolled steel plates of examples No. 1 to No. 24, and it was found that it was also lower in when at damping performance.

In addition, in relation to comparative example No. 2, the stiffness D and the moment M of bending were evaluated by means of a bending test. As a result, the rolled steel plate of comparative example No. 2 turned out to be the same as example No. 1 in mass W, but was less in terms of stiffness D and bending moment M. In comparative example No. 2, the processed plate material that was deformed according to a Poisson deformation during a bend deformation was used as a core layer, while example No. 1 in which the present invention was applied use wire grates as a core layer. Consequently, the deformation of the core layer was separated from the Poisson deformation, and therefore the bond strength of the laminated steel plates works and Young's modulus and the elastic limit increased. It is speculated that this effect is caused by the previous result.

The stiffness D and the bending moment M of the rolled steel plate of comparative example No. e were small compared to those of example No. 1. It is speculated that this is due to the carbon content of the steel wires. of the wire grid No. 10 was less than 0.24% by mass, and the tensile strength of the core layer was insufficient.

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In addition, in the laminated steel plate of comparative example No. 4, by means of the U-bending, there was a collapse towards the core layer of the surface layer steel plates (holes of the surface layer steel plates in holes of the core layer) and a fracture from the end portion of the surface layer steel plates, and processing validity was not retained. It is speculated that this is because the opening of the wire grid No. 11 was ten times the thickness of the surface layer steel plates, and a stress concentration occurred in a portion located above the holes in the plates of surface coating steel.

In addition, in the rolled steel plates of comparative examples No. 5 and No. 6, the thickness of all rolled steel plates was designated so that they had a bending moment substantially in the same plastic region as example No. 1 with the expression (viii), although in the actual measure it was lower than that of example No. 1. As a result of the analysis of the parts of the bending test of comparative examples No. 5 and No. 6, 70% of the core layer was resin in the laminated steel plate of comparative example No. 5 and the reinforcing fibers were not continuous, and therefore the shear strain resistance was lower than that in example No. 1. It is speculated that , as a result, the shear deformation of the core layer caused a maximum displacement of 1.5 mm (ten times that of example No. 1) on the surface layer steel plates of the upper and lower faces, and this displacement decreased the bending moment in the region pl astic In addition, in relation to comparative example No. 6, in addition to the fact that the resin part was only 50% of the core layer, there were no reinforcing fibers, and therefore there was a displacement that was much greater than the example Comparative No. 5. It is speculated that this displacement decreased the bending moment in the plastic region.

M (example N ° 1) = 1/4 (Ts ((ts + tc) 2 -tc2)) - Tc (tc2)) ... (viii)

In addition, in relation to the rolled steel plate of comparative example No. 7, the heat resistant stability of a U-curved processed product was evaluated. As a result, resin losses of an end portion of the steel plate, and a defect of form appeared.

In the foregoing, preferred embodiments of the present invention have been described with reference to the accompanying drawings, although it is not necessary to mention that the present invention is not limited to such examples. It is evident that a person skilled in the art is capable of designing various examples of variations and modifications within the scope described in the claims, and it should be understood that such examples of course belong to the technical scope of the present invention.

In accordance with the present invention, it is possible to provide a laminated steel plate that is light, very sharp and resistant to shocks, and that also combines a damping and manageability performance in terms of shearing, bending, deep drawing, extension and similar, as well as form stability after being processed.

LIST OF REFERENCE SYMBOLS

The reference symbols used in the description are detailed below:

 one

 rolled steel plate,

 5 (5A, 5B)

 steel plate (surface layer),

 10

 core layer,

 eleven

 grid wire group,

 13

 resin sheet,

 111

 vertical thread,

 113

 horizontal thread,

 115

 hole (grid)

 117

 ligation in oblique direction (thread),

 ts

 thickness of a surface layer steel plate

 tc

 thickness of a core layer,

 Wl, Wh

 opening,

 p

 step (grid), and

 d

 thread diameter

Claims (13)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 60 1. A rolled steel plate, comprising: a core layer that includes a wire group formed in a grid form using wires, holes surrounded by the wires, and a resin sheet; Y steel plates attached respectively to both sides of the core layer, where the threads have a tensile strength of 601 MPa or more, an opening of the grid wire group, defined by a long side of a rectangle that has a maximum area and that internally touches a hole, is equal to or less than ten Sometimes the thickness of the steel plates, and the threads are metallic, inorganic or organic threads. 2. The rolled steel plate according to claim 1, wherein the tensile strength of the wires is 1000 MPa or greater. 3. The rolled steel plate according to claim 1, wherein The opening of the grid wire group is equal to or less than 3.5 times the thickness of the steel plates. 4. The rolled steel plate according to claim 1, wherein The opening of the grid wire group is equal to or greater than 0.1 times the thickness of the steel plates. 5. The rolled steel plate according to claim 3, wherein The opening of the grid wire group is equal to or greater than 0.5 times and equal to or less than 1 time the thickness of the steel plates. 6. The rolled steel plate according to claim 1, wherein a base material of the resin sheet is foam. 7. The rolled steel plate according to claim 1, wherein the core layer and the steel plates are bonded with an adhesive, a shear bond strength of the adhesive and steel plates is 30 N / cm2 or greater, and A module G 'of adhesive storage at 100 ° C to 160 ° C is 0.05 MPa or greater and 100 MPa or less. 8. The rolled steel plate according to claim 1, wherein bundles of threads are added in an oblique direction with respect to the vertical threads and the horizontal threads. 9. The laminated steel plate according to claim 8, wherein the group of threads is a square grid, and The oblique direction is a direction that forms 45 ° with respect to the directions of the vertical threads and the horizontal threads. 10. The rolled steel plate according to claim 1, wherein the core layer is formed by the groups of threads rolled in n (n is an integer of 2 or greater) layers, and the direction of the threads that form the groups of threads of each layer is displaced in a certain direction by an angle of 360 / 3n or more and 360 / n or less between the thread groups of adjacent layers, to laminate the thread groups of respective layers. 11. The rolled steel plate according to claim 10, wherein The core layer is formed by groups of laminated threads in 2 layers up to 20 layers. 12. The rolled steel plate according to claim 1, wherein the core layer has three or more of the groups of wires, and between two groups of adjacent wires arbitrarily selected from three or more of the wire groups, the opening of the grid wire group disposed on a farther side with respect to a central position in a direction of the thickness of the core layer is more smaller than the opening of the group of grid threads arranged on a closer side. 13. The rolled steel plate according to claim 1, wherein the core layer has a plurality of groups of wires, and the plurality of the groups of threads are joined together by means of a union or interlacing in solid phase.